Title: Reinforcement learning for online adaptation of model predictive controllers: Application to a selective catalytic reduction unit

Journal Article · · Computers and Chemical Engineering

Here we present a novel application of reinforcement learning (RL) for online dynamic tuning of model predictive controllers (MPC). Applying a state-action-reward-state-action (SARSA) algorithm for temporal difference learning with a control-specific reward function improves the error tracking performance of a standard MPC formulation. The proposed RL approach is also readily adaptable to other MPCs, or entirely different control approaches. Practical details for the implementation of the RL-MPC algorithm are also presented. The proposed algorithm is applied to a case study of controlling nitrogen oxide (NOx) emissions in an industrial selective catalytic reduction (SCR) unit, a control problem characterized by significant nonlinearity and time delay. Along with an RL-MPC formulation for NOx control, another MPC is proposed to mitigate ammonia slip and decrease ammonia consumption in the SCR. Results showing the efficacy of the RL-MPC for NOx control through learning and implementation on the nonlinear SCR dynamic model are presented.

Research Organization:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)
Sponsoring Organization:
USDOE Office of Fossil Energy (FE)
OSTI ID:
1856318
Journal Information:
Computers and Chemical Engineering, Journal Name: Computers and Chemical Engineering Journal Issue: None Vol. 160; ISSN 0098-1354
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

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